Labour leader refuses to say if individual donors disclosed or attributed as a trust.
Labour leader David Cunliffe used an "agent arrangement" to take donations to his leadership campaign last November and is refusing to say whether he has disclosed individual donors in the MPs' register of financial interests or whether they were disclosed as being from a trust.
The returns for the Register of Pecuniary Interests were due last Friday, and Mr Cunliffe said his return met both the rules of the register, which requires disclosure of donations of more than $500, and those of the Labour Party, which said all donations would be confidential.
He refused to say how he had met both rules, or whether he had declared donations as being from a trust rather than the original donors.
But he confirmed his campaign was run through an "agent arrangement" rather than taking donations directly. He sought a legal opinion before filing his return and defended the use of trusts.
"In the event donations are made to a trust, the trustee will have information about donations which a candidate or campaign team won't have. So [if] there is a trust involved, it will be the donations of the trust to the campaign that are declared, as per the rules. If there is a trust, trustees owe obligations of confidentiality."
Of his rivals for the job, Shane Jones said he had disclosed all donations of more than $500, and the donors, and Grant Robertson said he did not receive any individual donations of more than $500.
The register will be published within three months.
In 2007, Labour changed electoral finance rules to stop National filtering large anonymous donations through trusts. Grants made through a trust must now be disclosed separately if larger than the disclosable limit of $15,000 to a party or $1500 for an individual candidate.
Mr Cunliffe said there was "nothing at all" to embarrass him in his return.
"It does appear there is a difference between the rules of the party and the rules of the Pecuniary Interests Register. MPs are bound to satisfy both. I'm confident that to the best of my knowledge I have done so, and the results will be in public view to the extent required by the Pecuniary Interests Register."
Mr Cunliffe also said Labour was likely to raise the issue with the standing orders committee, a cross-party group of MPs which decides on the rules for the register.
"It's quite clear that having primary-style elections is new and not something that has been explicitly foreseen before in the register rules. It does raise a number of legal technicalities over the match between internal party rules and the rules of the standing orders.
"It would be better for everybody if they were aligned."